cvs re-export/import, take 2, friday 10pm.

[Luka <luka@MIT.EDU>]

this time with feeling.  and a good chance of success.

key reminder points for y'all:

- after this operation any/all checked out copies of walkthru (and its subdirs)
  that you have around will have incorrect cvs versioning data and will need to
  get removed and checked out clean in order for cvs ops on them to work at all.

  (there are some hacks you can do if it turns out you do need to do cvs work on
  an old tree after i do this operation.  if that applies to you, come see me and
  i'll make suggestions case-by-case.... (the sooner the better!))

- cvs log history prior to this operation will no longer appear on the new module's
  files.  this is presumed to be OK since we are at a fair in-between point of
  development, and old history CAN still be accessed if needed by simply going to
  the archival tree instead of the new current one.

- empty dirs will disappear.  (which *would* be standard behavior if cvs were a
  better system.)  if you're still not using -P, you may be surprised.

so, try and quiesce your development as much as practical in the next, um,
20 hours, and definitely don't do anything with cvs after 10pm tonight (fri) until
i say it's clear again.  i'll probably sit around and do fairly harsh testing
before calling it good, and won't email a play by play, but if you are eager to be
doing work friday-night/sat-morn let me know and i will be more verbose about when
the tree is probably-good again vs. definitely-good.

sorry i couldn't get all this done earlier, when we were more quiescent overall,
but i think it's still not too late to get it out of the way reasonably, for the
next many years, so let's do it.

as always, any questions/concerns, ask me at will.

-pl